5.7


**Modification of Aircraft**.  Lessee shall not make or permit to be made any modification, alteration, improvement, or addition to the Aircraft without the express written consent of Lessor, except for those modifications, alterations, improvements, or additions that are necessary to comply with any applicable Airworthiness Directive or mandatory manufacturer’s service bulletin.  


  



5.8


**Fines, Penalties, and Forfeitures**.  Lessee shall be solely responsible for any fines, penalties, or forfeitures  relating in any manner to the operation, maintenance, or use of the Aircraft by Lessee under this Agreement while in Lessee’s possession for valid business reasons.


  



**SECTION 6.  RETURN OF AIRCRAFT**


  



6.1


**Return**.  On the last day of the Term or the date of earlier termination hereof, Lessee shall return the Aircraft to Lessor by delivering the same to Lessor at the Operating Base, fully equipped with all Engines and Parts installed thereon.  


  



6.2


**Condition of Aircraft**.  The Aircraft at the time of its return to Lessor, shall have, and be in compliance with, a current valid certificate of airworthiness issued by the FAA, and shall be airworthy according to manufacturer’s specifications and FAA regulations, shall have been maintained and repaired in accordance with the provisions of this Agreement, and shall be in the same condition as it was in when Lessee took possession on the Effective Date of this Agreement, ordinary wear and tear excepted. 


  



6.3